What We Talkin' About

The Blueprint 3 Jay Z
References "The Godfather" which means to set up mattresses for foot soldiers to sleep on in a hideout before getting the call to go to war.
He's talking about these tough guys broken down, crying themselves to sleep
Refers to the rapper Jaz-O, Jay-Z's "mentor turned arch nemisis", who could've signed with Rocafella, but didn't because he thought the contract was unfair.
Jay Z was one of Obam's Endorsments when he was running for President in 2008. Obama later then got elected and became the first black president
I'm happy to help him anytime he calls me on the phone.
in this line Jay addresses the fact that his references to his troubled past aren't intended for glorification like with other, more naive rappers, but rather for artistic and storytelling purposes only
indicating that he will not engage in a war of words with rappers The Game or Jim Jones, or ex-partner Damon Dash
In lines previous to this one, Jay says dudes are always on his lap (on his d***). He proclaiming that they need to get off his lap because he's not Santa Claus. Santa Claus has beard, Jigga doesn't, he's white, Jigga's not.
this lyric suggests wannabe gangstas who pretend to be tough by showing their guns in video clips they record and post on video sharing site youtube.com are not actually dangerous, but are considered a joke (a real thug wouldn't record himself like that)
Jay is claiming he is tired of answering questions about his occurances with rapper The Game, Interscope founder Jimmy Iovine, and his old Roc partner Damon Dash.